What might a grey reef shark and a coral reef have to do with you? Or how could a bonnethead shark and a sea-grass meadow matter? You might be surprised to know that our jobs, food security, medicines, the sanctity of our spirituality and the strength of our cultures – even how we will survive in a changing climate – are all connected to these sharks and the health of their habitats.
Since more than one-third of all sharks are threatened by overfishing, the global demand for shark meat and fins needs to be regulated if we are to keep our seas sustainable. That is why more than 60 species of sharks have been proposed for listing by the Convention on the International Trade in Endangered Species of Wild Fauna and Flora (CITES) this year. At least 20 of these species are destined for Appendix II, a move that will introduce monitoring of the trade and make it more transparent so that these sharks are not pushed into extinction. If the proposals are adopted, managing the international trade in requiem and hammerhead sharks, as well as guitarfishes (a proposal for later adoption), will bring 90% of the shark fin trade under regulation. The 19th meeting of the Conference of Parties to CITES will take place in November this year, when 184 nations will meet to decide how we trade threatened and endangered species. Ahead of it, we’re asking what this means for sharks, for our seas – and for us.
The Convention on the International Trade in Endangered Species of Wild Fauna and Flora (CITES) is an agreement between governments to prevent the extinction of plants and animals by ensuring that the trade in their products is regulated and sustainable. International cooperation is necessary when dealing with products that travel across borders, since the regulations in one country may not apply in another. There are now 184 countries that are members of CITES.
Animals and plants are listed on CITES according to three different appendices – Appendix I, II and III – that each indicate a different threat level. Each applies different levels of trade control and therefore offers different levels of protection. Appendix I offers the highest level of protection and is reserved for species threatened with extinction, as trade in these products is only permitted under special circumstances. For example, sawfishes and giant guitarfishes are listed on Appendix I. Appendix II offers protection for species whose trade must be regulated to avert the worsening of the populations’ status. Thresher and oceanic whitetip sharks are listed on Appendix II. Countries may approach other CITES Parties to protect species that are under threat within their borders by listing them on Appendix III. Many freshwater rays and stingrays are listed on Appendix III, such as the smooth back river stingray and the ocellate river stingray.
Sharks face many threats to their survival, including overfishing, habitat loss, pollution, climate change and direct persecution. Of these, overfishing is the single greatest threat. Sharks are caught for food, for their products (liver oil, skin, cartilage, fins) and as incidental ‘bycatch’, where the target is in fact another species or a teleost (a bony fish, such as a tuna, barracuda or grouper).
We use different conservation management tools to address each of these threats. Some tools can address multiple issues (a marine protected area, for example, can help overfished populations to recover, protect vulnerable habitats and conserve genetic diversity to help populations become more resilient to climate change), but when the key issue driving declines in a species is overexploitation for trade, the recommended tool is a CITES listing.
The first shark species were listed on CITES in 2003 when the basking shark and whale shark were added to Appendix II. Listing shark species on CITES Appendix II means that countries trading in shark products need to be able to demonstrate that the trade is legal, sustainable and can be traced. Nations must submit non-detriment findings, which means they must be able to demonstrate that trading a species will not endanger its survival, before a permit for trade can be granted. The process is well explained by Sarah Fowler in an episode of The Whole Tooth podcast.
A major flaw in the efficacy of CITES for sharks has been the inability to address the mixing of listed and non-listed species’ fins and products in international trade. Where certain species look alike, or have fins (or other products) that are indistinguishable when dried and traded, listed species have crept back into the trade. CITES regulations applying to them are circumvented because they are labelled as non-listed species, and enforcement at the border cannot determine which species are actually being traded. Trade in Endangered species, therefore, continues as illegal trade. Likewise, non-listed species may even become more heavily persecuted, leading to their decline. Addressing this particular issue could make CITES more effective for sharks.
With at least 56 species described in the family, requiem sharks can be found finning their way through the freshwater systems of the Ganges and Brahmaputra in India, nosing along the tropical reefs of the Caribbean, growing up in mangroves and coastal bays or hunting on shallow coastal reefs.
Known as the Carcharhinidae, requiem sharks make up the largest shark family and one that is considered among the most prominent and important in our oceans. They dominate in tropical waters, inhabit coastal continental shelves and waters offshore and can even be found in the subtropics and in temperate seas. Some, like the Ganges shark, even live in freshwater rivers and lakes. Others, like the bull shark, can tolerate both marine and freshwater and move from the ocean into estuaries and up rivers. Divers will be well acquainted with this family, as its members are very commonly seen, making up the most diverse and abundant group of sharks on coral reefs around the world. From whitetip reef sharks to bull sharks, oceanic whitetip sharks to silky, blue and Galápagos sharks, requiem sharks are encountered in commercial, subsistence and sport fisheries. They are important to tourism and recreation, and many of them are well studied.
Nineteen species of requiem shark are proposed for listing on CITES this year, all of which are listed as Endangered or Critically Endangered on the updated Red List of Threatened Species compiled by the International Union for the Conservation of Nature (IUCN). Requiem sharks are used as food and for their fins. They have been overfished for their liver oil, skin and cartilage, and they are the most commonly traded group of species in the international fin market. Many, but not all, species of requiem shark are threatened with extinction. However, the products of all the different species are difficult to distinguish. Therefore, the entire remainder of the Carcharhinidae family has been included in the proposal to list on Appendix II, as look-alike species that are included in an annexure. This move comes in a bid to address the longstanding hindrance to CITES efficacy: the mixing of listed and non-listed species products in circulation.
The unwieldy head shapes of the family Sphyrnidae are unmistakable. Several large-bodied hammerhead sharks have already been listed on Appendix II (the scalloped, great and smooth hammerheads), but the smaller bonnethead shark and its kin (all the remaining species of the Sphyrnidae family) have been proposed for addition this year. The bonnethead shark loves shallow coastal habitats such as sea-grass meadows, mangroves, estuaries and reefs. Five other small-bodied hammerhead species also exist and although the Endangered bonnethead is the lead species proposed for Appendix II, the entire group will be listed as look-alikes.
A staggering 89% of hammerhead species and 68% of requiem sharks are threatened with extinction. Both groups are heavily traded for their fins, among other products. Seventy per cent of shark species found in the Hong Kong fin market (the world’s largest) are listed as Critically Endangered, Endangered or Threatened in IUCN Red List categories. However, only 25% of those threatened species being traded are listed on CITES. The numbers are such that it is likely that every shipment of fins that arrives at a border post contains threatened species. However, if the requiem and hammerhead sharks are listed on CITES, it would then mean that every container of shark products arriving at a border would contain CITES Appendix II species. Each container would need to have a permit and the current burden on border officials (who must search every shipment to check for listed species) would be reduced. It would also mean that the entire fin trade could be better monitored.
Coral reefs and sea-grass meadows are two superpowered ocean ecosystems. They are also the important homes of most requiem sharks and the bonnethead shark. As populations of these sharks dwindle, the role that they play in these ecosystems is lost. The trouble is that humans also need coral reefs; they provide food, generate income, and help to buffer the worst effects of increasingly violent coastal storms, saving lives and infrastructure and reducing the cost of adaptation to climate change. Seagrasses are a cryptic weapon for combating climate change, helping to absorb excess carbon dioxide in the atmosphere. Requiem and hammerhead sharks play a role in regulating prey species, cycling nutrients and maintaining the food web in these ecosystems.
Worryingly, a global survey of coral reefs has shown that 20% of reef sharks (the majority of which fall into the requiem shark family) are functionally extinct on coral reefs. This means that their population numbers have fallen so low that the effects of the role they play in the ecosystem can no longer be seen.
The effects of the earth’s changing climate, however, are already visible and the urgent need to mitigate their worst impacts has been communicated. We can’t afford to lose the groups of sharks that help to keep some of our most important and vulnerable marine habitats functioning. If we lose requiem and hammerhead sharks, we stand to lose food security, livelihoods and our best chance of mitigating climate change.
The 19th CITES COP will be held in Panama City, Panama, from 14 to 25 November and more than 40 countries, led by the government of Panama, have supported the move to list requiem and small-bodied hammerhead sharks at the conference. Among the supporting nations are the Dominican Republic, Ecuador, Colombia, El Salvador, Seychelles, the Maldives, Bangladesh, Sri Lanka, Gabon, Israel, the United Kingdom, Syria and the European Union with its 27 member states. While voting for sharks at CITES falls to governments, understanding the wider context and advocating for requiem sharks, hammerhead sharks and their critical habitats will help all of us to work to secure a future for sharks and for ourselves.
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